<template>
  <div>
    <h2>TsNews</h2>
    <button @click="flag = false">{{ flag }}</button>
    <span v-if="flag" v-css>hello span1</span>
    <button @click="num++">{{ num }}</button>
  </div>
</template>
<script>
export default {
  data() {
    return {
      num: 0,
      flag: true
    }
  }
}
</script>